Merging many objects
We can shallowly merge objects without having to type out all properties by hand.
Read full articlePlucking properties from an array of objects
JavaScriptAll snippets in this category →
Posted on July 18, 2020One of the more common tasks when mapping over arrays in JavaScript is extracting properties from objects. Instead of using individual arrow functions, we can create a reusable helper function that does the plucking for us.
const countries = [
{ name: "France", capital: "Paris" },
{ name: "Spain", capital: "Madrid" },
{ name: "Italy", capital: "Rome" }
]
// we can extract the attributes with individual arrow functions
countries.map(country => country.name) // ⇒ ["France", "Spain", "Italy"]
countries.map(country => country.capital) // ⇒ ["Paris", "Madrid", "Rome"]
// this function allows us to write that arrow function shorter
const pluck = property => element => element[property]
countries.map(pluck("name")) // ⇒ ["France", "Spain", "Italy"]
countries.map(pluck("capital")) // ⇒ ["Paris", "Madrid", "Rome"]const countries = [
{ name: "France", capital: "Paris" },
{ name: "Spain", capital: "Madrid" },
{ name: "Italy", capital: "Rome" }
]
// we can extract the attributes with individual arrow functions
countries.map(country => country.name) // ⇒ ["France", "Spain", "Italy"]
countries.map(country => country.capital) // ⇒ ["Paris", "Madrid", "Rome"]
// this function allows us to write that arrow function shorter
const pluck = property => element => element[property]
countries.map(pluck("name")) // ⇒ ["France", "Spain", "Italy"]
countries.map(pluck("capital")) // ⇒ ["Paris", "Madrid", "Rome"]const countries = [
{ name: "France", capital: "Paris" },
{ name: "Spain", capital: "Madrid" },
{ name: "Italy", capital: "Rome" }
]
// we can extract the attributes with individual arrow functions
countries.map(country => country.name) // ⇒ ["France", "Spain", "Italy"]
countries.map(country => country.capital) // ⇒ ["Paris", "Madrid", "Rome"]
// this function allows us to write that arrow function shorter
const pluck = property => element => element[property]
countries.map(pluck("name")) // ⇒ ["France", "Spain", "Italy"]
countries.map(pluck("capital")) // ⇒ ["Paris", "Madrid", "Rome"]const countries = [
{ name: "France", capital: "Paris" },
{ name: "Spain", capital: "Madrid" },
{ name: "Italy", capital: "Rome" }
]
// we can extract the attributes with individual arrow functions
countries.map(country => country.name) // ⇒ ["France", "Spain", "Italy"]
countries.map(country => country.capital) // ⇒ ["Paris", "Madrid", "Rome"]
// this function allows us to write that arrow function shorter
const pluck = property => element => element[property]
countries.map(pluck("name")) // ⇒ ["France", "Spain", "Italy"]
countries.map(pluck("capital")) // ⇒ ["Paris", "Madrid", "Rome"]Continue reading
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